813Guardrail and Barrier

Guardrail and Barrier

813.1MGS/Corrugated Metal Beam Rail

1 For rail elements and terminal sections, provide and use 12-gage [2.51 mm], corrugated steel sheet beams in accordance with AASHTO M 180, Type II, Class A with rail post holes punched at half post spacing as shown in the contract.

813.2Guardrail Hardware

1 For guardrails and barriers, ensure the provision and use of hardware galvanized in accordance with Subsection 501.4.1.25, Galvanizing, and Subsection 815.14, Galvanized Coating. For bridge rail connections, guardrail, median barrier, and box beam splice connections, provide and use bolts in accordance with ASTM F 3125, Grade A325 [A325M]; provide and use other bolts, washers, fittings, and accessories in accordance with ASTM A 307, grade A. Provide and use wire rope or wire cable in accordance with Subsection 811.3, Wire Rope or Wire Cable.

813.3Box Beam Barrier

1 For box beam barriers, provide and use rail elements made from tubing in accordance with ASTM A 500 grade A or B; provide and use other structural steel elements in accordance with ASTM A 36 [ASTM A 36M] and galvanized in accordance with Subsection 501.4.1.25, Galvanizing, and Subsection 815.14, Galvanized Coating. Ensure that galvanized bolts thread easily into nuts on the splice plates.

813.4MGS Guardrail (Weathering Steel) and Corrugated Beam Guardrail (Self -

Oxidizing)

1 For self-oxidizing guardrail elements, terminals, anchorages, and hardware (except reflector tabs and bolts), provide and use unpainted, ungalvanized, blast- cleaned, dry steel. Provide rail elements made of corrugated steel sheet beams in accordance with AASHTO M 180, type IV, class A, with rail post holes punched at half post spacing as shown in the contract and as modified here. For all components, including hardware, ensure the provision and use of “weathering” steel in accordance with Table 813.4-1, Weathering Steel: Chemical Composition Requirements.

Guardrail and Barrier SECTION 813

Table 813.4-1 Weathering Steel: Chemical Composition Requirements Chemical % (Heat Analysis) Carbon 0.12, max. Manganese 0.20 to 0.50 Phosphorus 0.07 to 0.15 Sulfur 0.05, max. Silicon 0.25 to 0.75 Copper 0.25 to 0.55 Chromium 0.30 to 1.25 Nickel 0.65, max.

2 The department will allow the use of steel not in accordance with T able 813.4-1, Weathering Steel: Chemical Composition Requirements, if given certification that the proposed alternative steel has a corrosive resistance of at least four times that of carbon steel with a maximum copper content of 0.02 percent or twice that of carbon steel with a copper content from 0.25 to 0.55 percent.

3 For beam rails, ensure the use of sheet steel in accordance with ASTM A 606, type 4; the sheet may be in coils or cut lengths when corrugated.

Do not allow foreign material to contact steel surfaces. Ensure that parts are placed during shipment to allow free drainage and air circulation on the surfaces.

4 Provide and use retroreflector tabs, nuts, and bolts made of steel meeting the requirements in previous paragraphs, ASTM A 36 [ASTM A 36M], or other acceptable steel galvanized in accordance with Subsection 501.4.1.25, Galvanizing, and Subsection

815.14, Galvanized Coating

813.5Wyoming Box Beam End Terminal for Guardrails

813.5.1 Steel Components

1 Ensure that steel components used in fabricating Wyoming Box-Beam End Terminals

Subsection 815.14, Galvanized Coating, with corners, edges, and burrs ground smooth before galvanization. Ensure that the inner rail, impact head, and steel spacer slide smoothly and freely inside the outer rail for their full length of travel. Correct warping caused by welding or fabrication to ensure a loose fit. Instead of galvanization, the intermediate spacer may be shop painted with two coats of zinc-rich paint.

Guardrail and Barrier SECTION 813

813.5.2 Rubber Stops

1 For rubber stops in WYBETs, ensure the provision and use of hard rubber in accordance with AASHTO Standard Specifications for Highway Bridges Division II , roadway rumble strips or of an approved equal.

813.5.3 Composite Tubes

813.5.3.1 General

1 For use in WYBETs, ensure the provision of fiberglass-and-epoxy composite material in the following elements:

mm].

mm].

2 Cut tubes to the specified length, leaving both ends of each tube with neat tulips

points at each end; do not over-cut.

813.5.3.2 General Properties for Composite Tube Materials

1 Ensure that tubes are manufactured using the pultrusion process, that they consist of a glass-fiber-reinforced resin matrix with a glass to resin ratio of approximately 1:1, that the resin consists of isophthallic polyester, and that the glass reinforcement includes the following:

of other reinforcement fibers;

2 Ensure also that the composite material is in accordance with T able 813.5.3.-1, Mechanical Property Requirements: Composite Material.

Guardrail and Barrier SECTION 813

Table 813.5.3-1 Mechanical Property Requirements: Composite Material Property Requirements Ultimate Tensile Strength: Longitudinal Coupon 30,000 psi [205 MPa] Transverse Coupon 7,000 psi [48 MPa] Full Section in Bending 20,000 psi [138MPa] Ultimate Compressive Strength: Longitudinal Coupon 30,000 psi [205 MPa] Transverse Coupon 15,000 psi [102 MPa] Full Section in Bending 20,000 psi [138MPa] Ultimate Shear Strength 4,500 psi [31 MPa] Ultimate Breaking Strength 30,000 psi [205 MPa] Modulus of Elasticity: Full Beam Section in Bending 2.5 × 106 psi [17 000 MPa] Barcol Hardness 50

813.5.3.3 Crush Force Characteristics

1 Ensure that the composite tubes for WYBETs possess static energy dissipation properties in accordance with Table 813.5.3-2, Static Energy Dissipation Property Limits: Composite Tubes.

Table 813.5.3-2 Static Energy Dissipation Property Limits: Composite Tubes Property Limits Average of 3 Test Specimens Each Individual Test Specimen Stage 1 Tube Average Crush Force, Fa 19± 3 kips [85± 13 kN] 19± 5 kips [85± 22 kN] Max. Compressive Force, P 26 kips [116 kN] 28.5 kips [127 kN] Stage 2 Tube Average Crush Force, Fa 40± 4 kips [178± 18 kN] 40± 8 kips [178± 63 kN] Max. Compressive Force, P 55 kips [245 kN] 60 kips [267 kN]

2 Definitions of the average crush force (Fa), and maximum compressive force (P), are contained in Figure 813.5.3-1, Static Crush Test: Pultruded Fiberglass Tube. Determine the average crush force based on crush forces from 6 in to 14 in [150 mm to 355 mm] of crush; determine the maximum compressive force between 3.5 in and 6 in [90 mm to 150 mm] of crush.

Guardrail and Barrier SECTION 813

Force [kN]

Force (Kips)

Guardrail and Barrier SECTION 813

813.5.3.4 Test Procedures

1 Ensure the provision and use of composite tubes with the specified energy dissipation properties by using static compressive testing procedures performed as follows:

one each from the beginning, middle, and end of the tubes’ production run.

long in one end and caps on both ends.

along the tube’s longitudinal axis and centered under the loading head.

or displacement of at least 14 in [355 mm]. If the testing machine has insufficient stroke to crush the specimen in one continuous application, crush in stages, with a crush length of at least 6 in [150 mm] for each stage.

813.6Guardrail Posts

813.6.1 General

1 For guardrails, ensure that wood posts are cut from sound, growing trees of the species and with the ratings indicated for the intended use. For both wood and metal, ensure the provision and use of posts in accordance with Table 813.6.1-1, Guardrail Posts.

Guardrail and Barrier SECTION 813

Table 813.6.1-1 Guardrail Posts Post Designation Allowable Section Allowable Material Type and Grade Standard W-Beam Guardrail Post 6 in × 8 in [150 mm × 200 mm](1) Douglas Fir-Larch (P & T No. 1) Southern Yellow Pine (P & T No. 1) 8 in × 8 in [200 mm × 200 mm] Lodgepole Pine (P & T No. 1) Ponderosa Pine (P & T No. 1) 6 in x 8 in [150 mm x 200mm](1) Lodgepole Pine (P & T No.1) 8 in [200 mm] round Douglas Fir-Larch (P & T No. 1) Southern Yellow Pine (P & T No. 1) Lodgepole Pine (P & T No. 1) Ponderosa Pine (P & T No. 1) W 6 × 9 (2) ASTM A 6 (ASTM A 36 Steel) [ASTM A 6M (ASTM A 36M Steel)] Transition Post 10 in [250 mm] Round (3) Douglas Fir-Larch (P & T No. 1) Southern Yellow Pine (P & T No. 1) Lodgepole Pine (P & T No. 1) Ponderosa Pine (P & T No. 1) CRT Post 6 in × 8 in [150 mm × 200 mm](1) Douglas Fir-Larch (P & T No. 1) Southern Yellow Pine (P & T No. 1) BCT Post 6 in × 8 in [150 mm × 200 mm](1) Douglas Fir-Larch (P & T No. 1) Southern Yellow Pine (P & T No. 1) SAS only WYBET & WYBET MB Post #1 8 in × 6 in [200 mm × 150 mm](1) Douglas Fir-Larch (P & T No. 1) Southern Yellow Pine (P & T No. 1) SAS only

813.6.2 Wood Posts

1 Ensure that wooden posts and blocks for guardrails are treated in accordance with American Wood Protection Association (AWPA) Standard U1 to the requirements of Use Category 4B (UC4B) and certificates and reports thereof are submitted, in accordance with Section 817, Structural Timber and Lumber.

Guardrail and Barrier SECTION 813

813.6.2.1 Round Posts

1 Provide and use decay-free posts as follows:

wider than ½ in [12 mm] or longer than 1½ in [38 mm];

for the full post length and no wider than ¼ in [6 mm] or deeper than 2 in [50 mm] through the bolt hole;

in diameter, per 6 ft [2 m] of post length;

post length; and

2 in [50 mm]; trim allowable scars.

813.6.2.2 Dimensioned Posts and Blocks

1 For timber posts and blocks, provide as rough sawn or surfaced four sides (S4S).

813.6.3 Steel Posts

1 For steel guardrail posts, provide and use in the specified length and section, in accordance with ASTM A 36 [ASTM A 36M], and galvanized in accordance with AASHTO M 111 [AASHTO M 111M].